New solid and hollow, magnetic and non-magnetic, organic-inorganic monodispersed hybrid microspheres: synthesis and characterization

摘要

Hybrid microspheres usually consist of core micro-spheres coated with shell microspheres of substan-tially smaller diameter (nanoparticles) and of similar or different chemical composition. Hybrid micro-spheres may have a significantly higher surface area, different morphology and different surface chemical composition from those of the core microspheres. The coating of the nanoparticles on the core particles can be formed either by direct surface reactions or by controlled precipitation of the coating material in the form of nanoparticles on the surface of the suspended core microspheres [1—3]. Previous studies have described the use of these methods for the synthesis of hybrid microspheres composed of polystyrene microspheres coated with polyacrolein nanoparticles [1], and for the coating of different core substrates with a variety of shell materials, e.g. iron oxide colloids with uniform layers of silica [2], cationic polystyrene latex with uniform layers of yttrium basic carbonate and spindle type hematite with uniform coatings of silica or zirconium hydrous oxide [3].